1. Field of the Invention
This invention relates in general to detecting flying objects, particularly to means for identifying the object based upon the flicker within the exhaust plume, and also based upon radiation characteristics of pressure waves created by supersonic components of the flying object.
2. Description of the Prior Art
Most military jets that are downed by an enemy are destroyed by missiles. The missiles may be either radar or infrared guided missiles. If the aircraft pilot detects the missile being fired at him, he can take counter measures. He can make tight maneuvers, and he could eject flares and metal chaff to confuse either heat or radar guided missiles.
The counter measures require that the pilot be able to detect the missile before it becomes too close for any counter measures to be taken. Once the missile is launched, the pilot has only about one second to detect it, and another two seconds to start the counter measures. Current systems do not provide adequate detection of the launching of a missile.
Modern aircraft are vulnerable to missiles because of active and passive missile guidance techniques. The missile can passively lock onto the aircraft plume, hot metal parts and/or aircraft emissions such as radar and radio. Actively, the missile can be guided to the airplane by its own radar or infrared detection unit.
The aircraft is not now warned of the oncoming missile because radar warning techniques will give away the position of the aircraft. Present infrared techniques are useless because of the extremely high number of heat sources in the battle field, each of which looks like a missile to existing infrared systems. There may be other aircraft in the area, including friendly aircraft which produce heat. Ground fire could also cause a false alarm. Even if detected, the pilot must learn of the fired missile early enough to begin his counter measures.
Another problem exists when the flame of a missile goes out. Prior art devices may be attempting to detect heat of an exhaust plume of a missile. Missiles commonly, however, will burn out before reaching their target. This detection problem exists not only for military jets, but also for defensive systems for land targets.